1. Field of the Invention
The present invention relates generally to an image display and a method of treating a surface of a face panel used for the same.
2. Related Background Art
Face panels of image displays such as cathode-ray tubes, liquid crystal displays, and plasma displays are provided with surface coatings for reducing the reflection of outside light, static electricity, or the like.
In order to reduce the reflection of outside light, for example, the following methods can be used. In one method, as shown in FIG. 10, a coating film 14 with irregularities allowing light to scatter is provided on the surface of a face panel 2 by a spray coating method in which a coating material is sprayed on the surface of a face panel. In another method, at least two layers of coating films are formed by a spin coating method in which a coating material is spread over the surface of a face panel while the face panel is rotated, and thus at least two layers of coating films 15a and 15b causing light interference are provided as shown in FIG. 11. Furthermore, in order to utilize two effects of the interference and scattering of light together, recently, the following method also is used. That is, on the two layers of coating films 15a and 15b formed by the spin coating method, a third coating film 16 with surface irregularities further is provided by the spray coating method as shown in FIG. 12.
However, the above-mentioned conventional methods have the following problems.
In the method of providing a layer with surface irregularities on an outer surface of a panel by the spray coating method to scatter outside light, a high effect of reducing reflection is provided. Recently, however, this method tends not to be preferred. The reason is that the irregularities of the film cause an image to be displayed to be blurred and thus a high-resolution image quality cannot be obtained, or the film allows outside light to be reflected diffusively and thus the whole face panel looks whitish, which results in the deterioration in image contrast.
In the method of providing two layers of interference films by the spin coating method or further providing a layer with surface irregularities by the spray coating method on the two layers formed by the spin coating method, there is a problem in that the material cost is high. This is because coating materials are used in larger amounts than those of the coating material actually applied so as to be spread uniformly by the spin coating method and surplus coating materials that have not been applied are wasted, which results in a low material utilization rate. Particularly, for the formation of two layers of films, generally, an expensive conductive material is used as a material of the first layer to provide an antistatic effect and an electromagnetic wave shielding effect. Moreover, when the utilization rate of this material is low, the material cost further increases, which has been a problem.
Therefore, it is an object of the present invention to provide a treatment method for efficiently obtaining a face panel having antireflection and antistatic effects and allowing high-resolution images to be obtained, and to provide an image display with the face panel.
In order to solve the above-mentioned problems, a method of treating a surface of a face panel for an image display according to the present invention includes forming a film on the surface using coating materials. The film is formed of at least two layers and includes a first layer formed by a spray coating method and a second layer formed by a spin coating method to be superposed on the first layer.
This allows the upper layer to have a smooth surface.
In the method of treating a surface of a face panel for an image display according to the present invention, preferably, the coating material used for forming the first layer contains no binder component.
This allows the first layer to have a smooth surface.
In the method of treating a surface of a face panel for an image display according to the present invention, preferably, the first layer has a mean surface roughness of less than 0.20 xcexcm before the second layer is formed. In this context, the xe2x80x9cmean surface roughnessxe2x80x9d denotes a center line average height Ra.
This allows the second layer to have a smooth surface.
Furthermore, in the method of treating a surface of a face panel for an image display according to the present invention, preferably, the first layer has brittleness before the second layer is formed.
According to this, the first layer alone tends not to coagulate in a state with surface irregularities and thus has a smooth surface. In addition, the first layer allows a coating material of an upper layer easily to soak thereinto.
In the method of treating a surface of a face panel for an image display according to the present invention, preferably, the coating material used for forming the second layer is made of a material to react irreversibly.
This allows the first and second layers to coagulate to form a coating film with high hardness and adhesiveness.
An image display of the present invention includes a face panel with a film formed on its surface using coating materials. The film is formed of at least two layers and includes a first layer formed by a spray coating method and a second layer formed by a spin coating method to be superposed on the first layer.
According to this configuration, an image display can be obtained that has a face panel providing high contrast and allows a high-resolution image quality to be obtained.